Objective: Demonstrating clinical benefit of higher doses of inhaled corticosteroids in asthma is frequently problematic owing to their relatively flat dose-response curve in this condition. In this study we compared the efficacy and safety of a fourfold difference in the dose of ciclesonide-ciclesonide 320 microg twice daily (CIC640) versus ciclesonide 160 microg once daily (CIC160)-in patients with severe persistent asthma.
Methods: Patients with bronchial asthma (6 months) were included in this randomized, double-blind study. After receiving fluticasone propionate 250 microg twice daily during run-in, patients were randomized to CIC160 (n=339) or CIC640 (n=341) for 12 weeks. Primary endpoints were time to first asthma exacerbation and forced expiratory volume in 1s (FEV(1)). Secondary endpoints included other lung function variables, asthma symptom scores and rescue medication use (RMU).
Results: Asthma exacerbations occurred in 12.7% of patients receiving CIC160 and 6.7% receiving CIC640. CIC640 was superior for time to first exacerbation (p=0.0050, one-sided). FEV(1) increased significantly with CIC160 and CIC640 (least squares mean+/-SE of mean: 269+/-31 and 332+/-31 mL, respectively; p<0.0001), with no significant difference between groups. Change in % predicted FEV(1) and morning peak expiratory flow (PEF) were significantly higher with CIC640 (p<0.05). Asthma symptom score sums and RMU decreased in both groups; CIC640 was statistically superior (p=0.0108 and 0.0005, respectively). No unexpected adverse events were reported in either group and the majority of the events reported were mild or moderate in intensity. No significant changes in serum cortisol were observed from the baseline to the study end. Small decreases in creatinine-adjusted 24h urine cortisol levels from baseline were seen in both the treatment groups, which, due to the large patient numbers, were statistically significant (p<0.05); however, no dose-response effect was seen and the difference between groups was not significant (p=0.7892).
Conclusion: CIC640 was superior to CIC160 for time to first exacerbation, % predicted FEV1, morning PEF, asthma symptom score sum and RMU in patients with severe asthma; both doses had similar tolerability profiles and no significant changes in serum cortisol were seen in either treatment group.